Traditional printing devices rely on a mechanically operated carriage to transport a print head in a linear direction as other mechanics advance a medium in an orthogonal direction. As the print head moves over the medium an image may be laid down. Portable printers have been developed through technologies that reduce the size of the operating mechanics. However, the principles of providing relative movement between the print head and medium remain the same as traditional printing devices. Accordingly, these mechanics limit the reduction of size of the printer as well as the material that may be used as the medium.
Handheld printing devices have been developed that ostensibly allow an operator to manipulate a handheld device over a medium in order to print an image onto the medium. However, these devices are challenged by the unpredictable and nonlinear movement of the device by the operator. The variations of operator movement, including rotation of the device itself, make it difficult to determine the precise location of the print head. This type of positioning error may have deleterious effects of the quality of the printed image.
Certain handheld scanners have been developed for acquiring an image from a target media. During a scan, image data is recorded by image sensors along with positioning data by positioning sensors, which bracket the image sensors. The accumulated image data is position-tagged and recorded as distorted image data. Once the distorted image data has been acquired, it will be processed to provide a rectified image that corrects for rotational distortions. This rectification process further relies on overlapping regions of acquired image data to facilitate the stitching of the final image.
While this process may work in a scanning scenario, a printing scenario presents other challenges. For example, in a printing operation the positioning of a handheld printing device may not be postponed until after a medium has been fully scanned. Furthermore, stitching of a captured image may also not be available.